The development of various voice over IP protocols such as the H.323 Recommendation and the Session Initiation Protocol (SIP) has led to increased interest in multimedia conferencing. In such conferencing, typically, a more or less central server or other device manages the conference and maintains the various communications paths to computers or other client devices being used by parties to participate in the conference. Parties to the conference may be able to communicate via voice and/or video through the server and their client devices.
Instant messaging can provide an added dimension to multimedia conferences. In addition to allowing text chatting, instant messaging systems such as the Microsoft Windows Messenger™ system can allow for transfer of files, document sharing and collaboration, collaborative whiteboarding, and even voice and video. A complete multimedia conference can involve multiple voice and video streams, the transfer of files, marking-up of documents, and whiteboarding.
When a party attempts to call into or otherwise join a conference, the party must be authenticated or their permission to the join the conference validated. In traditional communication systems, this may be done by a password provided by the party or via use of a trust relationship. However, distributing and entering passwords may complicate the process and a trust relationship may not be easily verified. In addition, maintaining and updating a shared database may be complex and does not eliminate the ability of a party to guess a valid identifier that may allow access to a conference.
As such, there is a need for a system and method for insuring that only authorized parties or allowed to join a conference and/or for validating a potential party as being allowed to join a conference.